What about gradings? How would the grading examiner ask for a technique without naming it according to standard convention?

Also, the teaching style might vary from instructor to instructor. Where I train, 90% of the time the techniques are demonstrated (and named according to the Japanese terminology) then we go and practice them. However, one of our instructors is quite fond of reversing this if everyone in the class that day has at least a few months of experience - he'll call out an attack/technique, see what we do in response, and then show us how it should be done.

I don't really see any problem with naming the techniques in Japanese. In all walks of life - martial arts, sport, dance, work, study... everything has its own specific terminology that the people involved understand, worldwide. Could be in any language, or a completely new set of words. Japanese is the original language of Aikido; the terminology is already there. Why not keep it?